Blue Moon Diamond sells for world record $48.4m

The rare and flawless Blue Moon Diamond sold for 48.6m Swiss francs (£31.9m, $48.4 million) to a Hong Kong buyer on Wednesday (11 November), setting a world record for a gemstone at auction, Sothebys said. The cushion-shaped diamond, mounted on a ring, has the top grading of fancy vivid blue and weighs 12.03 carats. It had a pre-sale estimate of $35-55m. The previous record was held by the Graff Pink of 24.78 carats, sold by Sothebys for $46.2m in November 2010. Nov 12, 2015

CO2 levels hit record high for 30th year in a row

Greenhouse gas levels in the atmosphere reached a record high in 2014 as the relentless fuelling of climate change makes the planet more dangerous for future generations, the World Meteorological Organization (WMO) said on Monday (9 November). Nov 9, 2015